The objectives of the proposed research are the study of the mechanisms of triglyceride hydrolysis and the controlling factors which modulate it in adipose tissue as well as in heart and vascular tissue. The specific aims include separation and purification of the lipases in the whole tissue and its component parts, particularly the cytosol and the plasma membrane. The hormones (catecholamines, pituitary polypeptides, glucagon) which stimulate lipolysis will be examinated in the systems as well as the drugs which block their effects. The methods include enzyme isolation procedures, plasma cell isolation and subsequent study of the enzyme activities therein. The hormone and blocking drug studies include the study of dose-response curves in the presence and absence of the blocking drugs. All enzyme studies will include kinetic analyses.